Rocio Redon | Universidad Nacional Autónoma de México (original) (raw)
Papers by Rocio Redon
Additive Manufacturing and nanotechnology have been used as basic tools for the manufacture of na... more Additive Manufacturing and nanotechnology have been used as basic tools for the manufacture of nanostructured parts with magnetic properties to expand the variety of applications in additive processes by tank photopolymerization. Magnetic cobalt ferrite (CoFe2O4) and barium ferrite (BaFe12O19) nanoparticles with the size distribution of average value DTEM of 12 ± 2.95 nm and 37 ± 12.78 nm, respectively were generat-ed by hydroxide precipitation method. The dispersion of the nanoparticles on commercial resins (Anycubic Green and IRIX White resin) was obtained by mechanochemical reactions carried out in an agate mortar for 20 minutes, at room temperature and with limited exposure to light. The product of each reaction was placed in amber vials, also being kept in a box, to avoid contact with light. The photopolymerization process was carried out only at low concentrations (w/w % nanoparticles/resin) since, at high concentrations, there is no for-mation of pieces due to the high refractive index of ferrites. Raman shift spectroscopy of the final pieces showed that they contain the magnetic nanoparticles, with no apparent chemical changes. The EPR results of the pieces maintain the magnetic properties and apparently, they are not modified during the photopolymer-ization. Although significant differences were found in the dispersion process of the nanoparticles in each piece, we determined that the photopolymerization did not influence the structure and superparamagnetic behavior of ferrite nanoparticles during processing, and the magnetic properties were successfully transferred to the final 3D-printed magnetic obtained piece.
Journal of Coordination Chemistry, Feb 16, 2020
The formation of M@dendrimer composites (M ¼ platinum, iridium) is reported, at room temperature,... more The formation of M@dendrimer composites (M ¼ platinum, iridium) is reported, at room temperature, by mechanical milling of commercially available metallic precursors, sodium borohydride and small generation triazine-based dendrimers. After impurity removal, the composites are characterized by TEM showing spherical, worm-like or agglomerated nanoparticles depending upon the macromolecule stabilizer used. As a test of the surface activity of the metallic nanoparticles, the study of activity of the composites on the catalytic reduction of 4-nitrophenol show differences for each metal employed and suggest that surface of the NPs is not passivated by the presence of the stabilizer dendrimers.
Materials Chemistry and Physics, Nov 1, 2017
Abstract The obtaining of Pt(0), Ir(0), and Pt(0)-Ir(0) nanoparticles (NPs) is accomplished using... more Abstract The obtaining of Pt(0), Ir(0), and Pt(0)-Ir(0) nanoparticles (NPs) is accomplished using readily available metallic precursors through their reduction with NaBH 4 in solid state. Byproducts are removed by water/acetone washes and the influence of a final heat treatment step whether using air or nitrogen is compared with untreated samples. Characterization by PXRD shows NPs with diameters >10 nm and satisfactory results for unheated samples. Further analysis by XPS, TEM, and catalytic reduction of 4-nitrophenol provides evidence to confirm the presence of zero-valent NPs and the formation of an alloy in the Pt(0)-Ir(0).
ECS Journal of Solid State Science and Technology, Sep 1, 2022
In the present investigation, we show the effect of the addition of different salts on the respon... more In the present investigation, we show the effect of the addition of different salts on the response and enhancement of the Raman signal of triazines. To do this, we have used different monocharged anions (F−, Cl−, Br−, I−) and cations of the alkali metal family (Li+, Na+, K+); as supports, we have used four colloids of silver nanoparticles that were photoreduced with white, purple, blue, and green light filters, and as test analytes, we have used two different triazines (cyanuric acid and sodium trithiocyanurate). The highest Raman enhancement signals were produced by the combination of the smallest nanoparticles obtained (photo-irradiated with blue light) together with the halide anion (I−) and the alkali metal cation (K+). Regarding the analyte, sodium trithiocyanurate registered greater Surface-Enhanced Raman Scattering (SERS) improvements than cyanuric acid under these same conditions. Our research highlights the activating role of SERS played by highly polarizable monocharged ions (I− and K+), which facilitate the electronic transfer of metal to the analyte, improving the Raman signal markedly.
![Research paper thumbnail of ChemInform Abstract: High Yield Olefination of a Wide Scope of Aryl Chlorides Catalyzed by the Phosphinito Palladium PCP Pincer Complex: [PdCl{C6H3(O-P(iPr)2)2-2,6}]](https://attachments.academia-assets.com/117762860/thumbnails/1.jpg)
](ChemInform, Nov 28, 2000
iPr) 2) 2-2,6}].-The title compound efficiently catalyzes the olefination of aryl chlorides (I). ... more iPr) 2) 2-2,6}].-The title compound efficiently catalyzes the olefination of aryl chlorides (I). As a result of the high thermal stability of the catalyst the coupled products (III) are obtained in high yields. Compounds (III) exhibit only the (E)-configuration.-(MORALES-MORALES, DAVID; REDON, ROCIO;
Materials Today: Proceedings, 2016
POCOP pincers have been used as ligands to obtain robust coordination/organometallic compounds, u... more POCOP pincers have been used as ligands to obtain robust coordination/organometallic compounds, unfortunately the synthesis of these ligands is not the easiest one thus researchers work with similar but easier ligands. In this paper, we present the synthesis and obtaining of composites and organometallic POCOP-Pd(0)/Pd(0) nanoparticles and the comparison of their catalytic behavior. The organometallic POCOP-Pd(II) compounds were better catalysts than the composite Pd(0) nanoparticle-POCOP pincers with 80% yield compared with a 20% on the better yield of the composites. This might be because the nanoparticles do not have good protection from oxidation before the catalyst reaction. Another good result about this type of materials is that depending on the catalyst employed. Two different catalytic mechanisms can be applied depending on the material used: 1) the Pd(II)/Pd(IV) mechanism with organometallic Pd(II)-POCOP compounds and composites with Pd(II) nanoparticles with sodium citrate used as reducer, as catalysts; and 2) the Pd(0)/Pd(II) mechanism with Pd(0) nanoparticles obtained with sodium borohydride as reducer, as catalyst.
Journal of Cluster Science, Jan 30, 2021
The as-synthesized, europium-doped, yttrium orthovanadate nanostructures exhibited photoluminesce... more The as-synthesized, europium-doped, yttrium orthovanadate nanostructures exhibited photoluminescence properties that can vary based on the preparation conditions. All the samples exhibit red emissions, and the strongest emission band was observed at 620 nm and assigned to the 5 D 0 → 7 F 2 transition of Eu 3+ . The high intensity of the band is a consequence of the lack of inversion symmetry at the Eu 3+ site (D 2d symmetry) in the host lattice. The optimal europium doping concentration was 6 mol% for both preparation methods. These samples were annealed to obtain micro and nanoscale crystallite sizes in a range of 7.56 nm to 132.65 nm, and the emission spectra were obtained. The results revealed that the photoluminescence (PL) properties were dependent on crystallite size, the PL quantum yield measurements increased with increasing crystallite size. The introduction of the dopant ions induced changes in the TL glow curve structure and the kinetic properties, modifying the radiative recombination efficiency. The TL results suggest that both europium and europium-dysprosium doped YVO 4 nanocrystalline phosphor present good potential for β-irradiation dosimeter applications.
Catalysis Letters, 2021
Palladium(0) nanoparticles have been widely used in cross coupling reactions, including Heck reac... more Palladium(0) nanoparticles have been widely used in cross coupling reactions, including Heck reactions. For this study, we synthesized palladium(0) nanoparticles in colloidal suspension using different combinations of solvents and reducing methods under aerobic conditions. The variation in systems used to synthesize palladium(0) nanoparticles resulted in different nanoparticle sizes. To investigate whether the particle size had an effect on catalysis, we first used common Heck C–C cross-coupling reaction conditions (200 °C and 18 h). In addition, we omitted the use of stabilizing agents, other than the solvent and/or the anions in the initial nanoparticle synthesis, since the use of stabilizing agents adds cost and processing time to catalysis. All of the catalysts investigated worked in the cross coupling C–C Heck reaction, but yields did not show appreciable differences, as high temperature and long reaction times promote a high reduction of palladium(II). Therefore, we decided to work with a temperature and reaction time in which conversion would start to be observed (minimum reaction conditions). The experiments to determine minimum reaction conditions showed that this would be 120 °C and 10 h, therefore we used these conditions in Heck C–C cross-coupling reactions and all the palladium nanoparticle systems. The best C–C catalysis conversion was observed when N,N-dimethylformamide was used as solvent in the absence of reducing agent. This catalyst system resulted in the largest possible nanoparticles, which were kept in dispersion (did not precipitate out), showing that size is important in obtaining good yields in C–C Heck catalysis (where cocktail-type catalysis could explain the conversion). Nanoparticles of this size also act as a reservoir of soluble palladium species that behave as the true catalyst. The second best conversion was observed in N,N-dimethylformamide with sodium citrate, where citrate may have added extra protection, and since the palladium(0) nanoparticles were small, cocktail-type catalysis was not involved in obtaining high yields.
Recent Patents on Nanotechnology, 2020
: Since the elucidation of the leaching process by Mizoroki in the 1970s, the research focused on... more : Since the elucidation of the leaching process by Mizoroki in the 1970s, the research focused on this problem has increased. As a result, it has been discovered that the leached metals can not only hinder product yield, but they can also remain as contaminants of the final products. Thus, it can be concluded that metal leaching needs to be diminished or avoided more efficiently. This problem is important for industry and the environment because of the increases in costs and pollution. In 2014 we reported a brief review related to this important feature; now we would like to report on the latest findings on this important phenomenon, including an update on the mechanisms used to explain leaching and the reactions that support those mechanisms and including patents related to leaching in catalysis that have appeared in recent years.
Journal of Coordination Chemistry, 2016
Abstract An easy pathway to synthesize a variety of cupric oxide (CuO) nanoshapes by a one-step w... more Abstract An easy pathway to synthesize a variety of cupric oxide (CuO) nanoshapes by a one-step wet chemical method is reported. CuO nanoparticles and nanorods were obtained from CuCl2 in a mixture of water and DMSO in the absence of a base at room temperature. 1-D CuO nanostructures resembling wires inside tubes, or nanopea pods, were shaped when polyamidoamine (PAMAM) dendrimers of generation 2 (16-NH2 end groups) or 2.5 (32-COO− end groups) were added to the CuO colloids. The evolution in time of the different nanostructures was followed by UV–visible spectroscopy. The XRD patterns, Raman spectroscopy and high-resolution transmission electron microscopy show clear evidence that all nanoshapes obtained in this work are composed by CuO. This method is a simple, versatile, and economical alternative for the fabrication of CuO nanostructures and might provide a practical reference for the controlled synthesis of other nanoarchitectures.
Applied Surface Science, 2015
American journal of Chemical Research, 2017
Review Article AJCR 2017 1:5 Nanocomposites for Additive Manufacturing Additive Manufacturing (AM... more Review Article AJCR 2017 1:5 Nanocomposites for Additive Manufacturing Additive Manufacturing (AM) is one of several technological breakthroughs that is expected to lead the factories of the future, where conventional equipment will be transformed into smart and flexible systems, run by computers that will allow the fabrication of customized parts. Some authors have called AM the third industrial revolution, as it enables the accurate manufacture of pieces of virtually any shape in different scales, ranging from visual prototypes to specific functional end-use products at relatively short periods of time. Medical applications of AM is one of the key industries driving the innovations in the field, especially because of the possibility to fabricate products individually tailored to the patient's specific needs. The integration of nanomaterials in the area of AM has a lot of potential and there is a growing interest in academia and industry to explore for new developments. In this section, we examine some successful uses of nanocomposites in additive manufacturing processes.
… Section C: Crystal …, 1995
The unit cell of the title complex, [Cu(C3H6NO3)-(C12HsN2)(H20)]NO3, contains two nitrate anions ... more The unit cell of the title complex, [Cu(C3H6NO3)-(C12HsN2)(H20)]NO3, contains two nitrate anions and two complex cations, each with two chiral centers, one in the serine molecule and the other at the Cu ion. Each Cu ion displays slightly distorted square-pyramidal coordination, with the water molecule in the apical position and the base defined by the aliphatic N atom and one of the O atoms from the aminocarboxylate ligand and the two N atoms from the phenanthroline molecule. The relative position of the apical water molecule generates the chiral center at the Cu ion. In both molecules, the five-membered chelate ring defined by atoms N 1, C 12, C 11, N2 and Cu is roughly planar, while the ring defined by atoms N3, C13, C14, O1 and Cu has a distorted half-chair conformation. Comment Our study of the anticancer properties of several mixed phenanthroline-aminocarboxylate complexes led us to prepare and crystallize the complex [Cu(H20)(Lser)(phen)]NO3
Inorganica chimica acta, 2002
The formation of vinylic C---C bonds from the palladium catalyzed coupling of aryl bromides, iodi... more The formation of vinylic C---C bonds from the palladium catalyzed coupling of aryl bromides, iodides, and triflates with alkenes (the Heck reaction) is one of the 'true power tools of contemporary organic synthesis' [1], [1](a), [1](b), [1](c), [1](d), [1](e), [1](f) and [1](g). However, the ...
Polyhedron, 2001
Treatment of the dim chloride allyl-palladium complex [(h 3-C 3 H 5)Pd(m-Cl) 2 Pd(h 3-C 3 H 5)] w... more Treatment of the dim chloride allyl-palladium complex [(h 3-C 3 H 5)Pd(m-Cl) 2 Pd(h 3-C 3 H 5)] with Pb(SR) 2 in acetone affords dinuclear fluorothiolate bridged complexes of the type [(h 3-C 3 H 5)Pd(m-SR) 2 Pd(h 3-C 3 H 5)] (R = C 6 F 5 , 1; C 6 HF 4-4, 2; C 6 H 4 F-2, 3; C 6 H 4 F-3, 4 and C 6 H 4 F-4, 5). Complex 1 reacts with para-substituted phosphines P(C 6 H 4 X-4) 3 to give the mononuclear perfluorobenzenethiolate complexes [Pd(SC 6 F 5)(h 3-C 3 H 5)(P(C 6 H 4 X-4) 3)] (X =F, 6; CF 3 , 7; OCH 3 , 8 and CH 3 , 9). The single crystal X-ray diffraction structure of [(h 3-C 3 H 5)Pd(m-SC 6 H 4 F-4) 2 Pd(h 3-C 3 H 5)] (5) has been resolved.
RSC Adv., 2016
Ruthenium is in the air: small Ru NPs are obtained by milling RuCl3, NaBH4 and polyphosphorhydraz... more Ruthenium is in the air: small Ru NPs are obtained by milling RuCl3, NaBH4 and polyphosphorhydrazone dendrons under air. The whole dendron structure is involved in the stabilization process. These NPs catalyze the selective hydrogenation of styrene.
[
Toxicol Appl Pharmacol, 2001
Treatment of the dim chloride allyl-palladium complex [(h 3-C 3 H 5)Pd(m-Cl) 2 Pd(h 3-C 3 H 5)] w... more Treatment of the dim chloride allyl-palladium complex [(h 3-C 3 H 5)Pd(m-Cl) 2 Pd(h 3-C 3 H 5)] with Pb(SR) 2 in acetone affords dinuclear fluorothiolate bridged complexes of the type [(h 3-C 3 H 5)Pd(m-SR) 2 Pd(h 3-C 3 H 5)] (R = C 6 F 5 , 1; C 6 HF 4-4, 2; C 6 H 4 F-2, 3; C 6 H 4 F-3, 4 and C 6 H 4 F-4, 5). Complex 1 reacts with para-substituted phosphines P(C 6 H 4 X-4) 3 to give the mononuclear perfluorobenzenethiolate complexes [Pd(SC 6 F 5)(h 3-C 3 H 5)(P(C 6 H 4 X-4) 3)] (X =F, 6; CF 3 , 7; OCH 3 , 8 and CH 3 , 9). The single crystal X-ray diffraction structure of [(h 3-C 3 H 5)Pd(m-SC 6 H 4 F-4) 2 Pd(h 3-C 3 H 5)] (5) has been resolved.
Additive Manufacturing and nanotechnology have been used as basic tools for the manufacture of na... more Additive Manufacturing and nanotechnology have been used as basic tools for the manufacture of nanostructured parts with magnetic properties to expand the variety of applications in additive processes by tank photopolymerization. Magnetic cobalt ferrite (CoFe2O4) and barium ferrite (BaFe12O19) nanoparticles with the size distribution of average value DTEM of 12 ± 2.95 nm and 37 ± 12.78 nm, respectively were generat-ed by hydroxide precipitation method. The dispersion of the nanoparticles on commercial resins (Anycubic Green and IRIX White resin) was obtained by mechanochemical reactions carried out in an agate mortar for 20 minutes, at room temperature and with limited exposure to light. The product of each reaction was placed in amber vials, also being kept in a box, to avoid contact with light. The photopolymerization process was carried out only at low concentrations (w/w % nanoparticles/resin) since, at high concentrations, there is no for-mation of pieces due to the high refractive index of ferrites. Raman shift spectroscopy of the final pieces showed that they contain the magnetic nanoparticles, with no apparent chemical changes. The EPR results of the pieces maintain the magnetic properties and apparently, they are not modified during the photopolymer-ization. Although significant differences were found in the dispersion process of the nanoparticles in each piece, we determined that the photopolymerization did not influence the structure and superparamagnetic behavior of ferrite nanoparticles during processing, and the magnetic properties were successfully transferred to the final 3D-printed magnetic obtained piece.
Journal of Coordination Chemistry, Feb 16, 2020
The formation of M@dendrimer composites (M ¼ platinum, iridium) is reported, at room temperature,... more The formation of M@dendrimer composites (M ¼ platinum, iridium) is reported, at room temperature, by mechanical milling of commercially available metallic precursors, sodium borohydride and small generation triazine-based dendrimers. After impurity removal, the composites are characterized by TEM showing spherical, worm-like or agglomerated nanoparticles depending upon the macromolecule stabilizer used. As a test of the surface activity of the metallic nanoparticles, the study of activity of the composites on the catalytic reduction of 4-nitrophenol show differences for each metal employed and suggest that surface of the NPs is not passivated by the presence of the stabilizer dendrimers.
Materials Chemistry and Physics, Nov 1, 2017
Abstract The obtaining of Pt(0), Ir(0), and Pt(0)-Ir(0) nanoparticles (NPs) is accomplished using... more Abstract The obtaining of Pt(0), Ir(0), and Pt(0)-Ir(0) nanoparticles (NPs) is accomplished using readily available metallic precursors through their reduction with NaBH 4 in solid state. Byproducts are removed by water/acetone washes and the influence of a final heat treatment step whether using air or nitrogen is compared with untreated samples. Characterization by PXRD shows NPs with diameters >10 nm and satisfactory results for unheated samples. Further analysis by XPS, TEM, and catalytic reduction of 4-nitrophenol provides evidence to confirm the presence of zero-valent NPs and the formation of an alloy in the Pt(0)-Ir(0).
ECS Journal of Solid State Science and Technology, Sep 1, 2022
In the present investigation, we show the effect of the addition of different salts on the respon... more In the present investigation, we show the effect of the addition of different salts on the response and enhancement of the Raman signal of triazines. To do this, we have used different monocharged anions (F−, Cl−, Br−, I−) and cations of the alkali metal family (Li+, Na+, K+); as supports, we have used four colloids of silver nanoparticles that were photoreduced with white, purple, blue, and green light filters, and as test analytes, we have used two different triazines (cyanuric acid and sodium trithiocyanurate). The highest Raman enhancement signals were produced by the combination of the smallest nanoparticles obtained (photo-irradiated with blue light) together with the halide anion (I−) and the alkali metal cation (K+). Regarding the analyte, sodium trithiocyanurate registered greater Surface-Enhanced Raman Scattering (SERS) improvements than cyanuric acid under these same conditions. Our research highlights the activating role of SERS played by highly polarizable monocharged ions (I− and K+), which facilitate the electronic transfer of metal to the analyte, improving the Raman signal markedly.
ChemInform, Nov 28, 2000
iPr) 2) 2-2,6}].-The title compound efficiently catalyzes the olefination of aryl chlorides (I). ... more iPr) 2) 2-2,6}].-The title compound efficiently catalyzes the olefination of aryl chlorides (I). As a result of the high thermal stability of the catalyst the coupled products (III) are obtained in high yields. Compounds (III) exhibit only the (E)-configuration.-(MORALES-MORALES, DAVID; REDON, ROCIO;
Materials Today: Proceedings, 2016
POCOP pincers have been used as ligands to obtain robust coordination/organometallic compounds, u... more POCOP pincers have been used as ligands to obtain robust coordination/organometallic compounds, unfortunately the synthesis of these ligands is not the easiest one thus researchers work with similar but easier ligands. In this paper, we present the synthesis and obtaining of composites and organometallic POCOP-Pd(0)/Pd(0) nanoparticles and the comparison of their catalytic behavior. The organometallic POCOP-Pd(II) compounds were better catalysts than the composite Pd(0) nanoparticle-POCOP pincers with 80% yield compared with a 20% on the better yield of the composites. This might be because the nanoparticles do not have good protection from oxidation before the catalyst reaction. Another good result about this type of materials is that depending on the catalyst employed. Two different catalytic mechanisms can be applied depending on the material used: 1) the Pd(II)/Pd(IV) mechanism with organometallic Pd(II)-POCOP compounds and composites with Pd(II) nanoparticles with sodium citrate used as reducer, as catalysts; and 2) the Pd(0)/Pd(II) mechanism with Pd(0) nanoparticles obtained with sodium borohydride as reducer, as catalyst.
Journal of Cluster Science, Jan 30, 2021
The as-synthesized, europium-doped, yttrium orthovanadate nanostructures exhibited photoluminesce... more The as-synthesized, europium-doped, yttrium orthovanadate nanostructures exhibited photoluminescence properties that can vary based on the preparation conditions. All the samples exhibit red emissions, and the strongest emission band was observed at 620 nm and assigned to the 5 D 0 → 7 F 2 transition of Eu 3+ . The high intensity of the band is a consequence of the lack of inversion symmetry at the Eu 3+ site (D 2d symmetry) in the host lattice. The optimal europium doping concentration was 6 mol% for both preparation methods. These samples were annealed to obtain micro and nanoscale crystallite sizes in a range of 7.56 nm to 132.65 nm, and the emission spectra were obtained. The results revealed that the photoluminescence (PL) properties were dependent on crystallite size, the PL quantum yield measurements increased with increasing crystallite size. The introduction of the dopant ions induced changes in the TL glow curve structure and the kinetic properties, modifying the radiative recombination efficiency. The TL results suggest that both europium and europium-dysprosium doped YVO 4 nanocrystalline phosphor present good potential for β-irradiation dosimeter applications.
Catalysis Letters, 2021
Palladium(0) nanoparticles have been widely used in cross coupling reactions, including Heck reac... more Palladium(0) nanoparticles have been widely used in cross coupling reactions, including Heck reactions. For this study, we synthesized palladium(0) nanoparticles in colloidal suspension using different combinations of solvents and reducing methods under aerobic conditions. The variation in systems used to synthesize palladium(0) nanoparticles resulted in different nanoparticle sizes. To investigate whether the particle size had an effect on catalysis, we first used common Heck C–C cross-coupling reaction conditions (200 °C and 18 h). In addition, we omitted the use of stabilizing agents, other than the solvent and/or the anions in the initial nanoparticle synthesis, since the use of stabilizing agents adds cost and processing time to catalysis. All of the catalysts investigated worked in the cross coupling C–C Heck reaction, but yields did not show appreciable differences, as high temperature and long reaction times promote a high reduction of palladium(II). Therefore, we decided to work with a temperature and reaction time in which conversion would start to be observed (minimum reaction conditions). The experiments to determine minimum reaction conditions showed that this would be 120 °C and 10 h, therefore we used these conditions in Heck C–C cross-coupling reactions and all the palladium nanoparticle systems. The best C–C catalysis conversion was observed when N,N-dimethylformamide was used as solvent in the absence of reducing agent. This catalyst system resulted in the largest possible nanoparticles, which were kept in dispersion (did not precipitate out), showing that size is important in obtaining good yields in C–C Heck catalysis (where cocktail-type catalysis could explain the conversion). Nanoparticles of this size also act as a reservoir of soluble palladium species that behave as the true catalyst. The second best conversion was observed in N,N-dimethylformamide with sodium citrate, where citrate may have added extra protection, and since the palladium(0) nanoparticles were small, cocktail-type catalysis was not involved in obtaining high yields.
Recent Patents on Nanotechnology, 2020
: Since the elucidation of the leaching process by Mizoroki in the 1970s, the research focused on... more : Since the elucidation of the leaching process by Mizoroki in the 1970s, the research focused on this problem has increased. As a result, it has been discovered that the leached metals can not only hinder product yield, but they can also remain as contaminants of the final products. Thus, it can be concluded that metal leaching needs to be diminished or avoided more efficiently. This problem is important for industry and the environment because of the increases in costs and pollution. In 2014 we reported a brief review related to this important feature; now we would like to report on the latest findings on this important phenomenon, including an update on the mechanisms used to explain leaching and the reactions that support those mechanisms and including patents related to leaching in catalysis that have appeared in recent years.
Journal of Coordination Chemistry, 2016
Abstract An easy pathway to synthesize a variety of cupric oxide (CuO) nanoshapes by a one-step w... more Abstract An easy pathway to synthesize a variety of cupric oxide (CuO) nanoshapes by a one-step wet chemical method is reported. CuO nanoparticles and nanorods were obtained from CuCl2 in a mixture of water and DMSO in the absence of a base at room temperature. 1-D CuO nanostructures resembling wires inside tubes, or nanopea pods, were shaped when polyamidoamine (PAMAM) dendrimers of generation 2 (16-NH2 end groups) or 2.5 (32-COO− end groups) were added to the CuO colloids. The evolution in time of the different nanostructures was followed by UV–visible spectroscopy. The XRD patterns, Raman spectroscopy and high-resolution transmission electron microscopy show clear evidence that all nanoshapes obtained in this work are composed by CuO. This method is a simple, versatile, and economical alternative for the fabrication of CuO nanostructures and might provide a practical reference for the controlled synthesis of other nanoarchitectures.
Applied Surface Science, 2015
American journal of Chemical Research, 2017
Review Article AJCR 2017 1:5 Nanocomposites for Additive Manufacturing Additive Manufacturing (AM... more Review Article AJCR 2017 1:5 Nanocomposites for Additive Manufacturing Additive Manufacturing (AM) is one of several technological breakthroughs that is expected to lead the factories of the future, where conventional equipment will be transformed into smart and flexible systems, run by computers that will allow the fabrication of customized parts. Some authors have called AM the third industrial revolution, as it enables the accurate manufacture of pieces of virtually any shape in different scales, ranging from visual prototypes to specific functional end-use products at relatively short periods of time. Medical applications of AM is one of the key industries driving the innovations in the field, especially because of the possibility to fabricate products individually tailored to the patient's specific needs. The integration of nanomaterials in the area of AM has a lot of potential and there is a growing interest in academia and industry to explore for new developments. In this section, we examine some successful uses of nanocomposites in additive manufacturing processes.
… Section C: Crystal …, 1995
The unit cell of the title complex, [Cu(C3H6NO3)-(C12HsN2)(H20)]NO3, contains two nitrate anions ... more The unit cell of the title complex, [Cu(C3H6NO3)-(C12HsN2)(H20)]NO3, contains two nitrate anions and two complex cations, each with two chiral centers, one in the serine molecule and the other at the Cu ion. Each Cu ion displays slightly distorted square-pyramidal coordination, with the water molecule in the apical position and the base defined by the aliphatic N atom and one of the O atoms from the aminocarboxylate ligand and the two N atoms from the phenanthroline molecule. The relative position of the apical water molecule generates the chiral center at the Cu ion. In both molecules, the five-membered chelate ring defined by atoms N 1, C 12, C 11, N2 and Cu is roughly planar, while the ring defined by atoms N3, C13, C14, O1 and Cu has a distorted half-chair conformation. Comment Our study of the anticancer properties of several mixed phenanthroline-aminocarboxylate complexes led us to prepare and crystallize the complex [Cu(H20)(Lser)(phen)]NO3
Inorganica chimica acta, 2002
The formation of vinylic C---C bonds from the palladium catalyzed coupling of aryl bromides, iodi... more The formation of vinylic C---C bonds from the palladium catalyzed coupling of aryl bromides, iodides, and triflates with alkenes (the Heck reaction) is one of the 'true power tools of contemporary organic synthesis' [1], [1](a), [1](b), [1](c), [1](d), [1](e), [1](f) and [1](g). However, the ...
Polyhedron, 2001
Treatment of the dim chloride allyl-palladium complex [(h 3-C 3 H 5)Pd(m-Cl) 2 Pd(h 3-C 3 H 5)] w... more Treatment of the dim chloride allyl-palladium complex [(h 3-C 3 H 5)Pd(m-Cl) 2 Pd(h 3-C 3 H 5)] with Pb(SR) 2 in acetone affords dinuclear fluorothiolate bridged complexes of the type [(h 3-C 3 H 5)Pd(m-SR) 2 Pd(h 3-C 3 H 5)] (R = C 6 F 5 , 1; C 6 HF 4-4, 2; C 6 H 4 F-2, 3; C 6 H 4 F-3, 4 and C 6 H 4 F-4, 5). Complex 1 reacts with para-substituted phosphines P(C 6 H 4 X-4) 3 to give the mononuclear perfluorobenzenethiolate complexes [Pd(SC 6 F 5)(h 3-C 3 H 5)(P(C 6 H 4 X-4) 3)] (X =F, 6; CF 3 , 7; OCH 3 , 8 and CH 3 , 9). The single crystal X-ray diffraction structure of [(h 3-C 3 H 5)Pd(m-SC 6 H 4 F-4) 2 Pd(h 3-C 3 H 5)] (5) has been resolved.
RSC Adv., 2016
Ruthenium is in the air: small Ru NPs are obtained by milling RuCl3, NaBH4 and polyphosphorhydraz... more Ruthenium is in the air: small Ru NPs are obtained by milling RuCl3, NaBH4 and polyphosphorhydrazone dendrons under air. The whole dendron structure is involved in the stabilization process. These NPs catalyze the selective hydrogenation of styrene.
[
Toxicol Appl Pharmacol, 2001
Treatment of the dim chloride allyl-palladium complex [(h 3-C 3 H 5)Pd(m-Cl) 2 Pd(h 3-C 3 H 5)] w... more Treatment of the dim chloride allyl-palladium complex [(h 3-C 3 H 5)Pd(m-Cl) 2 Pd(h 3-C 3 H 5)] with Pb(SR) 2 in acetone affords dinuclear fluorothiolate bridged complexes of the type [(h 3-C 3 H 5)Pd(m-SR) 2 Pd(h 3-C 3 H 5)] (R = C 6 F 5 , 1; C 6 HF 4-4, 2; C 6 H 4 F-2, 3; C 6 H 4 F-3, 4 and C 6 H 4 F-4, 5). Complex 1 reacts with para-substituted phosphines P(C 6 H 4 X-4) 3 to give the mononuclear perfluorobenzenethiolate complexes [Pd(SC 6 F 5)(h 3-C 3 H 5)(P(C 6 H 4 X-4) 3)] (X =F, 6; CF 3 , 7; OCH 3 , 8 and CH 3 , 9). The single crystal X-ray diffraction structure of [(h 3-C 3 H 5)Pd(m-SC 6 H 4 F-4) 2 Pd(h 3-C 3 H 5)] (5) has been resolved.